After Newtown, officials at the nonprofit Child Health and Development Institute of Connecticut said there has been a spike in requests from school employees across the state seeking training on recognizing the subtle signs of trauma that, left untreated, can be devastating to a child's long-term health.

The institute, which has long collaborated with the state Department of Children and Families on training mental health providers on trauma therapy, has been educating pediatricians for months on how to identify trauma symptoms in children so they can be referred for treatment.

Now school personnel, particularly school nurses, are learning about those symptoms.

A two-hour session held Wednesday at Hartford's Bulkeley High School drew about 125 school nurses, social workers such as LaPlante, and school psychologists from the area. Another training was held Thursday in Westport, and more sessions for school nurses are planned for the coming weeks in East Hampton, Hamden, Chaplin, Bloomfield, Waterford and Winsted, according to organizers.

One landmark national study has shown a link between adverse childhood experiences and lifelong social and health problems, including an increased risk for alcohol and drug abuse, sexually-transmitted diseases, depression, obesity, heart disease, diabetes and unemployment.

"What we're trying to do is make sure pediatric providers can identify those kids earlier, get them to the appropriate treatment and really break that cycle of victimization," said Robert Franks, a trauma expert and the institute's vice president of mental health initiatives.

At Bulkeley, Franks said several chronic symptoms of trauma — such as the inability to control impulses, difficulty falling asleep and decreased concentration — can often be misdiagnosed in children as attention deficit hyperactivity disorder or anxiety.

Experiencing sleep disruption and separation anxiety after the Newtown shooting, for example, are "normal reactions to an abnormal event," he said. But adults should become concerned when weeks or months have passed since the traumatic event and a child still struggles to get through a normal day.

Franks noted later that the institute has routinely screened minors as they head into the juvenile justice system, and has found that 80 to 90 percent of them have been exposed to trauma as children.

"There's well-established documentation about the cycle of being a victim and going on to be a perpetrator," he told the group. "So we really can see this issue of trauma as a public health issue, as an epidemic issue, that we really need to confront in our society ...